The rescue operation began about 8am on Tuesday after an emergency beacon was activated about 270 nautical miles (500 kilometres) east of Wollongong.

The 44-year-old Queensland yachtsman had reportedly left Sydney's northern beaches two weeks ago.

He was off the main shipping route and in a remote area of the ocean when his boat ran into trouble.

Because of the remote location, the Australian Maritime Safety Authority (AMSA) asked two commercial aircraft whose flight paths passed over the man's GPS position to check on the distressed yacht.

An Air Canada Boeing 777 heading to Sydney from Vancouver and an Air New Zealand A320 from Auckland confirmed the 11-metre yacht had been dismasted and was drifting in strong swells.

Canadian singer Jill Barber was on the Air Canada flight when passengers were reportedly asked to use binoculars to try to spot the boat.

In an email to a music news website, Barber wrote: "An eventful flight for sure!

"We did circle around the site a few times, and though I had a window seat I could not identify the boat myself . . . apparently it was very small and distant," she said.

Once the yachtsman's position was confirmed, AMSA was able to make contact with him.

Merchant ship ANL Benalla was diverted to the scene to provide protection from strong swells until the police launch Nemesis arrived about 4am yesterday and returned the man to Sydney.

His yacht was abandoned at sea and ships were warned to avoid the area.